Apparatuses and methods for timing-based power level control

Various types of medical systems and devices include external and implanted components that are coupled together during operation. As one example, people who have little or no natural hearing may benefit from a cochlear implant system that stimulates auditory nerves in ways that natural hearing mechanisms fail to stimulate for various reasons. A cochlear implant system may include external components such as a microphone for capturing an audio signal, a sound processor for generating stimulation parameters based on the audio signal, and a headpiece for wirelessly transmitting power and data associated with the stimulation parameters to a cochlear implant that applies electrical stimulation to a recipient of the cochlear implant system. In this example, the cochlear implant may include an electrode lead that has been inserted into a cochlea of the recipient and may wirelessly receive the power and data from the external components (e.g., the headpiece) and use this power and data to apply the desired electrical stimulation to the cochlea by way of the electrode lead. Other types of implanted medical devices and systems may operate in similar ways, with power and data similarly being transmitted wirelessly (i.e., transcutaneously) through the skin.

For any of these types of systems, it is desirable for power and data transmission to be efficient so as to minimize wasted power, extend battery life, reduce heat dissipation, and so forth. In certain examples, it would be desirable to gain such efficiencies using circuitry that is as unobtrusive (e.g., small, light, etc.) as possible. Unfortunately, conventional techniques for controlling power levels involve electrical components (e.g., buck converter circuits and associated passive elements such as capacitors and inductors, etc.) that tend to be relatively large, bulky, heavy, power-hungry, and/or otherwise unconducive to these and other design goals for the system.

Apparatuses and methods for timing-based power level control are described herein. As described above, medical systems and devices (e.g., cochlear implant systems and/or other medical systems and devices that handle power and data transfer in similar ways) may include one or more external components and one or more internal (implanted) components. The external components may be configured to generate and wirelessly transmit power and data for the implanted components to receive and use to accomplish the purposes of the medical device or system. For example, a headpiece may wirelessly transmit, to a cochlear implant device implanted within a recipient, a carrier signal that carries radio frequency (RF) power (e.g., power to be used by the cochlear implant to apply electrical stimulation to the recipient) as well as modulated stimulation data (e.g., data representative of stimulation parameters dictating how the electrical stimulation is to be applied).

As power and data are wirelessly transmitted in these types of systems, it may be desirable for the wireless transfer to be performed efficiently for various reasons described above. For example, it may be desirable to consistently provide enough power for the implanted component to be able to operate properly (e.g. to provide the appropriate amount of stimulation to the recipient, etc.) while, at the same time, not providing so much power that a significant amount of the power is wasted. One way to control the power level of a wireless transmission is to use an efficient RF power supply to generate and/or modulate the carrier signal at a particular voltage that provides a desired amount of power. For instance, a buck converter integrated circuit (IC) configured to control the voltage level of the carrier signal may be employed for this purpose. Unfortunately, as mentioned above, such ICs may require design compromises (e.g., due to the size or bulkiness of the ICs, the power they consume, etc.) and/or may be implemented with other devices (e.g., passive elements such as large capacitors, inductors, resistors, etc.) that themselves require such compromises.

To address these challenges, systems and methods described herein provide timing-based power level control so that voltage-based power level controllers (e.g., the buck converter IC described above or similar power supplies) and their associated passive elements may be eliminated or simplified, thereby reducing the size, weight, power consumption, and other such characteristics of the external parts of the system. As will be described in more detail below, timing-based power level control may operate by adjusting a timing profile of the carrier signal rather than a voltage profile of the signal. For example, while a voltage level of the carrier signal may remain at a particular level, the timing profile may be adjusted (e.g., by skipping pulses, by shortening pulses, or by other techniques described herein) in a manner that reduces the power level being transmitted while keeping the fundamental phase and frequency of the carrier signal the same. Methods and systems for timing-based power level control may function to transfer power alone, or may produce time-adjusted carrier signals onto which data is modulated (in various ways described herein) so as to transfer power and data together.

Systems and methods described herein may employ timing-based power level control as an alternative to, or in combination with, conventional voltage-based power level control, and in doing so may provide various benefits and advantages. As one example that was mentioned above, timing-based power level control mechanisms may allow certain power supply circuitry to be reduced, simplified, or even eliminated altogether. In many cases, this may improve battery life for the system; may allow the system to run cooler and more efficiently (since less power is wasted and less heat is generated); may allow external component design (e.g., headpiece design) to have more desirable characteristics for recipients (e.g., lighter, smaller, more inconspicuous, etc.); may reduce system costs; and may otherwise augment or improve the system characteristics. Other benefits may include reduced design time, more flexible products that may be updated in the field using software (e.g., to program new types of timing profiles to be used) rather than requiring hardware updates (which may be difficult or impractical to deploy after the product is released), facilitation of active and/or fully-integrated external components (e.g., headpieces that include power generation circuitry and/or sound processing circuitry rather than that circuitry being implemented in a separate sound processor component), and so forth.

Various specific embodiments will now be described in detail with reference to the figures. It will be understood that the specific embodiments described below are provided as non-limiting examples of how various novel and inventive principles may be applied in various situations. Additionally, it will be understood that other examples not explicitly described herein may also be captured by the scope of the claims set forth below. Systems and methods described herein for timing-based power level control may provide any of the benefits mentioned above, as well as various additional and/or alternative benefits that will be described and/or made apparent below.

1 FIG. 100 100 100 100 100 100 shows an illustrative timing-based power control apparatus(“apparatus”) that is configured to perform timing-based power level control in accordance with principles described herein. As will be described and illustrated in more detail below, apparatusmay be implemented as part of any suitable system or device to facilitate effective and efficient performance by that system or device. As one example, apparatusmay be included in an external component (e.g., a headpiece, etc.) of a medical system (e.g., a cochlear implant system) that operates using wireless transfer of power and/or data between the external component and an internal component (e.g., an implanted component such as a cochlear implant). Apparatusmay include any suitable circuitry to perform operations described herein. For example, power supply circuitry (e.g., RF power generators, etc.), passive circuitry (e.g., resistors, capacitors, inductors, etc.), logic circuitry (e.g., individual gates, combinatorial logic, etc.), memory or storage circuits (e.g., flip flops, solid-state memory, etc.), and/or more complex circuitry (e.g., microprocessors, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.), may all be used to implement apparatusin various cases as may serve a particular implementation.

100 102 104 102 106 104 108 106 108 106 108 106 106 106 As shown, apparatusmay include a signal generation circuit(e.g., signal generation circuitry implemented by any of the circuitry described above) and a power control circuit(e.g., power control circuitry implemented by any of the circuitry described above) that are communicatively coupled to one another. As will be described in more detail below, signal generation circuitmay be configured to generate a carrier signalfor wireless transmission of output power and output data, while power control circuitmay be configured to generate a time-adjusted versionof carrier signal. Time-adjusted versionof carrier signalmay also be referred to herein as time-adjusted carrier signal, but it will be understood that this time-adjusted version of carrier signalis generated based on carrier signaland is thus related to carrier signalin various ways (e.g., having the same voltage profile, fundamental frequency, and fundamental phase, but having a different timing profile and different fundamental amplitude so as to carry less power).

106 108 106 106 106 100 100 108 106 106 108 1 FIG. As one example of the relationship between carrier signaland time-adjusted carrier signal, carrier signalmay be associated with a first fundamental component having a particular frequency, a particular phase, and a first amplitude. This fundamental component may be a sinusoidal signal that is combined with various other sinusoidal signals (harmonic components, overtone components, etc.) to form carrier signal. The first amplitude of the fundamental component of carrier signalmay be associated with a maximum supported power level for the output power that apparatusgenerates as part of the wireless transmission. However, apparatusmay also receive timing control data (not explicitly shown in) that corresponds to a target power level for the output power that is lower than the maximum supported power level for the output power. Based on this timing control data, time-adjusted carrier signalmay be generated to maintain an amplitude of the carrier signal, but to have an adjusted timing profile as compared to carrier signal. For example, while carrier signalmay include a series of pulses generated at the particular frequency of the first fundamental component (e.g., forming a square wave with a 50% duty cycle), the timing profile of these pulses may be altered for time-adjusted carrier signalsuch as by periodically skipping pulses, altering the duty cycle of the pulses in certain ways, and so forth.

106 108 108 106 108 106 As a result of the timing profile changes from carrier signalto time-adjusted carrier signal, a second fundamental component associated with time-adjusted carrier signalmay have the same particular frequency and the same particular phase as carrier signal, but may have a second amplitude that is different than the first amplitude of the first fundamental component. Specifically, the second amplitude of the second fundamental of time-adjusted carrier signalmay be lower than the first amplitude and may be associated with the target power level for the output power (based on the timing control data). In order to preserve the frequency and phase of the first fundamental component while reducing the amplitude as the timing profile is adjusted, systems and methods described herein disclose methods for symmetrically shortening certain pulses from a series of pulses that may be included in carrier signal. As used herein, a pulse is “symmetrically shortened” when the duty cycle of the pulse is changed in a way that symmetrically moves the rising edge and the falling edge of a pulse inward toward one another by equal amounts or at an equal rate such that zero crossings of the fundamental component (and therefore the phase of the fundamental component) are preserved and maintained. Examples of symmetric shortening of pulses and illustrative ways in which this may be accomplished will be described in more detail below.

It will be understood that various advantages may arise from being able to reduce the amplitude of the fundamental component of the carrier signal while maintaining the frequency and phase of the carrier signal in the ways described herein. For example, if all the telemetry data (or all the telemetry data in a certain direction such as from the external component to the internal component of a medical system such as a cochlear implant system) is to be transmitted at a single frequency (e.g., a frequency for which legal authorization has been obtained from regulatory agencies or the like), it may be important for frequency and phase to remain consistent even if the fundamental amplitude (representative of the power level being transmitted by way of the carrier signal) is adjusted.

2 FIG. 2 FIG. 2 FIG. 2 FIG. 2 FIG. 2 FIG. 200 100 200 shows an illustrative methodfor timing-based power level control in accordance with principles described herein. Whileshows illustrative operations according to one embodiment, other embodiments may omit, add to, reorder, and/or modify any of the operations shown in. In some examples, multiple operations shown inor described in relation tomay be performed concurrently (e.g., in parallel) with one another, rather than being performed sequentially as illustrated and/or described. One or more of the operations shown inmay be performed by a timing-based power control apparatus such as apparatusand/or any implementation thereof. For instance, methodmay be performed by a headpiece of a cochlear implant system or other similar external component of another type of medical system described herein, or by other suitable systems or devices as may serve a particular implementation.

2 FIG. In some examples, the operations ofmay be performed in real time so as to provide, receive, process, and/or use signals and data described herein immediately as the signals (or data) are generated, updated, changed, exchanged, or otherwise become available. Moreover, certain operations described herein may involve real-time signals, real-time representations, real-time conditions, and/or other real-time circumstances. As used herein, “real time” will be understood to relate to data processing and/or other actions that are performed immediately, as well as conditions and/or circumstances that are accounted for as they exist in the moment when the processing or other actions are performed. For example, a real-time operation may refer to an operation that is performed immediately and without undue delay, even if it is not possible for there to be absolutely zero delay. Similarly, real-time signals, real-time data, real-time representations, real-time conditions, and so forth, will be understood to refer to data, representations, and conditions that relate to a present moment in time or a moment in time when decisions are being made and operations are being performed (e.g., even if after a short delay), such that the signals, data, representations, conditions, and so forth are temporally relevant to the decisions being made and/or the operations being performed.

202 204 200 206 208 100 Each of operationsandof method, along with certain conditionsandthat may be associated with these operations, will now be described in more detail as the operations may be performed by circuitry included within a timing-based power control apparatus (e.g., apparatusor an implementation thereof) or another suitable system or device.

202 102 100 106 206 202 206 202 202 106 106 2 FIG. At operation, a signal generation circuit (e.g., signal generation circuit) included in a timing-based power control apparatus (e.g., apparatus) may generate a carrier signal (e.g., carrier signal) for wireless transmission of output power and output data. As indicated by condition(drawn with dashed lines and connected to operationto indicate that conditionarises from or is otherwise associated with the performance of operation), the carrier signal generated at operationmay be associated with a first fundamental component having a particular frequency, a particular phase, and a first amplitude. As described above in relation to the first fundamental component of carrier signal, the first amplitude of the first component may be associated with a maximum supported power level for the output power (indicated as “max output power” in). For example, the maximum supported power level may be a power level that would be transmitted if carrier signalwas transmitted as a series of pulses with a 50% duty cycle (a square wave signal rather than a time-adjusted signal in which the timing profile is changed by skipping pulses, shortening pulses to less than 50% duty cycle, or the like).

204 104 108 At operation, a power control circuit (e.g., power control circuit) included in the timing-based power control apparatus may generate a time-adjusted version of the carrier signal (e.g., time-adjusted carrier signal) based on timing control data corresponding to a target power level for the output power. For example, the timing adjusted version of the carrier signal may correspond to a target power level that is lower than the maximum supported power level for the output power and that is configured to help optimize system efficiency in any of the ways described herein.

208 202 208 204 204 206 108 204 208 2 FIG. As indicated by condition(drawn with dashed lines and connected to operationto indicate that conditionarises from or is otherwise associated with the performance of operation), the time-adjusted version of the carrier signal generated at operationmay be associated with a second fundamental component having a same particular frequency and a same particular phase as the first fundamental component described in condition, but may have a second amplitude that is different. Specifically, as described above in relation to the second fundamental component of time-adjusted carrier signal, the second amplitude of the second fundamental component may be associated with a target power level that is less than the maximum supported power level for the output power (indicated as “target power level<max output power” in). For example, the target power level may be a power level that provides sufficient power to an internal component (e.g., a cochlear implant, etc.) without undue inefficiencies such as have been described. In other words, at operation, conditionshows that the time-adjusted version of the carrier signal may maintain an amplitude of the carrier signal while adjusting a timing profile of the carrier signal such that the second fundamental component associated with the time-adjusted version of the carrier signal has the particular frequency, the particular phase, and the second amplitude lower than the first amplitude and associated with the target power level for the output power.

3 FIG. 300 100 100 302 304 304 302 302 100 306 304 308 302 304 302 304 310 306 308 shows an illustrative configurationwithin which apparatusmay operate to perform timing-based power level control in accordance with principles described herein. Specifically, as shown, apparatusis included within an external componentthat is separated from an internal componentby a layer of skin, since internal componentmay be implanted within a recipient while external componentremains external to the recipient. Within external component, apparatusmay receive input datathat is to be transmitted (e.g., along with wireless RF power) to internal component, as well as data input representative of a target power levelthat is to be provided by external componentto internal component. External componentmay provide, through the skin of the recipient to be received at internal component, a wireless transmissionthat includes output data (e.g., the same data as input data) modulated onto a time-adjusted version of a carrier signal (e.g., a carrier signal that provides power at the designed target power level).

308 302 312 314 316 302 318 316 100 312 318 100 302 100 316 302 100 302 302 318 300 3 4 FIGS.and To adjust the timing profile of a default carrier signal to generate a time-adjusted version of the carrier signal that will provide target power level, external componentis shown to include a storage facilitythat includes, possibly among other data, timing control data packaged into one or more timing control datasets. Additionally, a batteryis shown to provide battery power (wired direct current (DC) power) to external componentand battery monitor circuitis shown to monitor the power level that is provided by batteryas that power level may change as the battery is consumed and recharged. A dashed line extending from apparatusto encompass storage facilityand battery monitor circuitis shown to indicate that these components may be included within apparatusin certain implementations while, in other implementations, they may be part of external componentbut considered to be separate from apparatus. Additionally, it will be understood that batterymay be included within external componentand/or apparatusin certain implementations, while being part of a separate external component in other implementations (e.g., included within a separate sound processor in an example in which external componentis implemented by a headpiece coupled to the sound processor). Each of the elements-of configurationwill now be described in more detail with reference to.

302 304 302 304 External componentand internal componentmay be any suitable components of a medical system or other stimulation system that operates with certain parts external to a recipient and other parts that are implanted. Such systems may be configured to provide various types of stimulation to the heart, the brain or spinal cord (or other segments of the nervous system), a particular muscle or muscle group, a sensory organ (e.g., the eyes or ears, etc.), or the like. For example, the stimulation system incorporating external componentand internal componentmay be implemented as a hearing system (e.g., a cochlear implant system that provides electrical stimulation to a cochlea of the recipient, an electroacoustic stimulation hearing system that provides a combination of electrical and acoustic stimulation to the recipient, another type of hearing system that provides vibrotactile bone conduction or other stimulation to the recipient, etc.), a neuromodulation system (e.g., a spinal cord stimulator, a sacral stimulator, etc.), or another suitable stimulation system (e.g., a cardiac pacemaker, etc.).

300 300 100 4 FIG. To provide a more specific example of a stimulation system that may implement configuration,shows an illustrative cochlear implant system that may implement configuration. Specifically, in this example, apparatusmay be implemented within an external headpiece included in a cochlear implant system that further includes an internal cochlear implant configured to receive a wireless transmission of output power and output data from the external headpiece when the internal cochlear implant is implanted within a recipient of the cochlear implant system and the external headpiece is external to the recipient.

4 FIG. 400 400 402 404 406 408 408 410 412 302 1 302 406 304 304 408 310 406 408 310 1 shows an exemplary cochlear implant systemin which two alternative external component scenarios (separated by a dashed line) are illustrated external to the skin (“External”), while a cochlear implant is illustrated internal to the skin (“Implanted”). Referring first to the scenario above the dashed line, cochlear implant systemis shown to include, in this implementation, a microphone, a sound processor, and a headpiecethat are external to the skin of the recipient and communicatively coupled to a cochlear implantimplanted within the recipient. Cochlear implantis shown to be coupled with an electrode leadhaving a plurality of electrodes. In this first implementation, an arrow labeled “-” indicates that external componentis to be understood to be implemented by headpiece, while an arrow labeled “” indicates that internal componentis to be understood to be implemented by cochlear implant. Additionally, as shown, wireless transmissionbetween headpieceand cochlear implantis represented by a connection labeled “-” for the first implementation.

402 402 402 404 402 406 404 Microphoneis configured to detect one or more audio signals (e.g., that include speech and/or any other type of sound) in an environment of the recipient. Microphonemay be implemented in any suitable manner. For example, microphonemay be implemented by a microphone that is configured to be placed within the concha of the ear near the entrance to the ear canal, such as a T-MIC™ microphone from Advanced Bionics. Such a microphone may be held within the concha of the ear near the entrance of the ear canal during normal operation by a boom or stalk that is attached to an ear hook configured to be selectively attached to sound processor. Additionally or alternatively, microphonemay be implemented by one or more microphones in or on headpiece, one or more microphones in or on a housing of sound processor, one or more beam-forming microphones, and/or any other suitable microphone as may serve a particular implementation.

404 404 404 Sound processormay be implemented by any suitable device that may be worn or carried by the recipient. For example, sound processormay be implemented by a behind-the-ear (BTE) unit configured to be worn behind and/or on top of an ear of the recipient. Additionally or alternatively, sound processormay be implemented by an off-the-ear unit (also referred to as a body worn device) configured to be worn or carried by the recipient away from the ear.

406 416 404 406 416 406 408 404 406 404 In certain examples, headpiecemay be implemented as a passive headpiece that receives, by way of a communication link(implemented by a cable or the like), a modulated RF signal from sound processor. In other examples, headpiecemay be implemented as an active headpiece that receives, by way of communication link, DC power and a baseband data signal. In the passive example, headpiecemay wirelessly transmit, to cochlear implant, the modulated RF signal received from sound processor, while, in the active example, headpiecemay both generate and transmit such a modulated RF signal based on the DC power and data signal received from sound processor.

406 404 408 406 408 406 406 408 404 408 310 1 In either case, headpiecemay include an external antenna (e.g., a coil and/or one or more wireless communication components) configured to facilitate selective wireless coupling of sound processorto cochlear implant. Headpiecemay additionally or alternatively be used to selectively and wirelessly couple any other external device to cochlear implant. To this end, headpiecemay be configured to be affixed to the recipient's head and positioned such that the external antenna housed within headpieceis communicatively coupled to a corresponding implantable antenna (which may also be implemented by a coil and/or one or more wireless communication components) included within or otherwise connected to cochlear implant. In this manner, input data (e.g., stimulation parameters, etc.) and/or power signals may be wirelessly and transcutaneously transmitted between sound processorand cochlear implantby way of wireless transmission-.

404 402 402 404 404 406 408 408 412 410 In operation, sound processormay receive an audio signal detected by microphoneby receiving a signal (e.g., an electrical signal) representative of the audio signal from microphone. Sound processormay additionally or alternatively receive the audio signal by way of any other suitable interface as described herein. Sound processormay process the audio signal in any of the ways described herein and transmit, by way of headpiece, stimulation parameters and power to cochlear implantto direct cochlear implantto apply electrical stimulation representative of the audio signal to the recipient by way of electrodeson electrode lead. For example, the stimulation parameters may be generated and provided in accordance with a particular sound processing program (e.g., program strategy) configured to account for particular conditions of the hearing environment, particular attributes and/or preferences of the recipient, and so forth.

400 418 404 404 418 402 310 310 2 310 1 302 2 418 302 406 An alternative implementation of cochlear implant systemis shown with different components below the dashed line on the external side of the skin. Specifically, in this case, the external headpiece may be implemented as an integrated headpieceor “one-piece system” that includes, together with a signal generation circuit and a power control circuit such as have been described, a sound processing circuit configured to perform the functionality described above for sound processor. For example, in contrast to the first implementation including the separate sound processor, integrated headpieceof this second implementation may be configured to generate, based on input audio data from a similar microphone, the output data wirelessly transmitted to the cochlear implant by way of wireless transmission(labeled as wireless transmission-in this second implementation to distinguish from wireless transmission-of the first implementation). As shown by a reference designator “-,” integrated headpiecemay be considered to be an alternative implementation of external componentthat may be used instead of headpiece.

418 402 400 100 418 418 406 406 418 In certain examples, integrated headpiecemay include one or more embedded microphones implementing microphone, a battery and associated power circuitry, and any other external circuitry used by cochlear implant system. In other examples, the sound processing circuitry and power/data transmission circuitry (e.g., including apparatus) may be included within integrated headpiecewhile a battery, microphone, and/or other components may still be housed separately from integrated headpiece(e.g., within a BTE external component or other such device). In either of these examples, as well as the example of the active implementation of headpiecedescribed above, it may be advantageous for RF power to not be transferred between a sound processor and a headpiece, as such transmission may generate unwanted emissions, cause unwanted power consumption, or otherwise be undesirable. However, it has conventionally be challenging to implement an integrated and/or active headpiece (such as the active implementation of headpieceor integrated headpiece) in part because of the weight and size of power circuitry that operates in the conventional ways mentioned above (e.g., using buck converters and associated passive elements to provide voltage-based power level control, etc.). Accordingly, methods and systems described herein for timing-based power level control that allow for weight and size of an active and/or integrated headpiece to be reduced may be especially advantageous for these implementations.

400 400 300 406 418 310 1 310 2 408 4 FIG. 4 FIG. 4 FIG. In either the first or second implementations of cochlear implant systemillustrated in, cochlear implant systemwill be understood to implement a medical system or other stimulation system such as described above in relation to configuration. In both implementations, the cochlear implant system will be understood to include: 1) a headpiece (e.g., headpieceor integrated headpiece) configured to be worn externally by a recipient of the cochlear implant system and to provide a wireless transmission (e.g., wireless transmission-or-) of output power and output data; 2) a cochlear implant (e.g., cochlear implant) configured to be implanted within the recipient and to receive the wireless transmission from the headpiece; 3) a signal generation circuit (not explicitly shown in) included within the headpiece and configured to generate a carrier signal for the wireless transmission, the carrier signal associated with a first fundamental component having a particular frequency, a particular phase, and a first amplitude associated with a maximum supported power level for the output power; and 4) a power control circuit (not explicitly shown in) included within the headpiece and configured to generate, based on timing control data corresponding to a target power level for the output power that is lower than the maximum supported power level for the output power, a time-adjusted version of the carrier signal that maintains an amplitude of the carrier signal and adjusts a timing profile of the carrier signal such that a second fundamental component associated with the time-adjusted version of the carrier signal has the particular frequency, the particular phase, and a second amplitude lower than the first amplitude and associated with the target power level for the output power.

3 FIG. 4 FIG. 306 304 306 306 310 304 306 100 Returning to, input datamay include any data that is to be transmitted to internal componentfor a particular implementation. For instance, in the cochlear implant system example illustrated in, input datamay be data representative of stimulation parameters that have been generated by the sound processor and are to be transmitted by the headpiece for use by the cochlear implant in applying stimulation to the recipient. In other examples, input datamay be other types of data that are to be transmitted as output data on wireless transmissionto internal component. In any of these cases, input datamay be transmitted by being modulated onto a carrier signal generated and modified (e.g., time adjusted) within apparatusin the ways described herein.

308 302 304 308 308 400 302 304 304 308 316 316 Target power levelmay be received from any suitable source and may indicate what power level is desirable for external componentto provide to internal componentunder particular circumstances. In certain examples, target power levelmay be relatively static. For instance, in certain examples, target power levelmay be based on one or more relatively static factors such as a program strategy used for the wireless transmission of output power and output data (e.g., a sound processing program utilized by the sound processor of a particular implementation of cochlear implant system, etc.), a physical distance between external componentand internal componentwhen the internal component is implanted within the recipient and the external component is external to the recipient (e.g., based on the thickness of the skin flap of the particular recipient, the exact placement of internal componentduring the implantation procedure, etc.), or the like. Additionally or alternatively, target power levelmay account for the current battery level of battery, which may stay relatively static but may decrease slowly as batteryis consumed and the DC voltage it provides is reduced.

308 308 In certain examples, target power levelmay be adjusted more dynamically based on factors that tend to change more quickly than the width of a skin flap or the voltage level provided by a battery. For instance, in the cochlear implant system example, target power levelmay vary with a volume of sound in the environment of the recipient (e.g., the magnitude of the audio signal being captured by the microphone) or another such factor that may dynamically change from moment to moment.

306 308 100 310 310 302 304 310 310 302 304 304 302 Based on input dataand target power level, apparatusmay generate output power and/or output data (e.g., data modulated onto the carrier signal carrying the output power) for wireless transmission. Wireless transmissionmay be transcutaneously provided from external componentto internal componentin any of the ways that have been described. Additionally, as indicated by the bidirectional nature of the arrow representing wireless transmission, it will be understood that wireless transmissionmay include both a forward telemetry aspect (e.g., RF power and data transmitted from external componentto internal component) as well as a backward telemetry aspect (e.g., data transmitted from internal componentback out to external component).

308 100 310 308 308 312 314 100 314 308 100 310 In certain implementations, timing control data configured to implement a particular target power levelmay be accessed by apparatusas part of generating wireless transmission. For example, as will be described and illustrated in more detail below, a timing control dataset may include data that facilitates the adjustment of an original carrier signal to generate the time-adjusted version of the carrier signal in a manner that provides the desired target power levelfor the output power. Accordingly, a library of potential timing control datasets corresponding to various potential values for target power levelmay be stored within a storage facilityas timing control datasetsand apparatusmay access a particular timing control datasetbased on target power levelas apparatusperforms operations to generate the time-adjusted version of the carrier signal used for wireless transmission.

312 314 308 302 304 314 314 308 100 314 312 Storage facilitymay be configured to maintain the plurality of timing control datasetscorresponding to the plurality of different target power levels for the output power, as shown. For a given target power level(e.g., for a given battery level, sound processing program, distance between external componentand internal component, etc.) the plurality of timing control datasetsmay include a particular timing control datasethaving timing control data corresponding to that target power level. As such, part of the generating of the time-adjusted version of the carrier signal performed by apparatusmay include selecting and accessing, by the power control circuit, the particular timing control datasetfrom storage facility.

314 100 308 308 314 312 308 Prior to the selecting and accessing of the particular timing control dataset(and as further part of the generating of the time-adjusted version of the carrier signal), the power control circuit of apparatusmay identify target power levelfor the output power. As mentioned above, this identified target power levelmay be based on at least one of a program strategy used for the wireless transmission of output power and output data, or a distance between the external and internal components of the medical system when the internal component is implanted within the recipient and the external component is external to the recipient. The power control circuit may select and access the particular timing control datasetfrom storage facilitybased on the identified target power level.

3 FIG. 302 318 316 316 100 318 100 316 Additionally or alternatively, as also mentioned above, the timing control data may be changed dynamically based on a detected battery level. For example, as shown in, external componentmay include a battery monitor circuitthat continuously or periodically detects a battery level of batteryas batterysupplies DC power to the signal generation circuit and the power control circuit of apparatus. Based on the battery level detected by battery monitor circuit, apparatusmay generate the time-adjusted version of the carrier signal differently in order to deliver the desired amount of power. For example, because the amplitude of the carrier signal may decrease as batteryis gradually consumed, a different timing profile for the time-adjusted version of the carrier signal may be required at a later time than was used at an earlier time to deliver the same amount of power (i.e., to create a fundamental component of the carrier signal with the same amplitude).

100 314 318 316 314 318 316 More specifically, the power control circuit of apparatusmay be configured to generate the time-adjusted version of the carrier signal based on one timing control datasetwhen battery monitor circuitdetects that the battery level of batteryis above a particular threshold. The power control circuit may also be configured to generate the time-adjusted version of the carrier signal based on a different timing control dataset(e.g., a timing control dataset corresponding to a different target power level for the output power) when battery monitor circuitdetects that the battery level of batteryis below the particular threshold.

5 9 FIGS.- 1 FIG. 5 9 FIGS.- 102 104 106 108 106 106 108 106 108 show illustrative aspects of carrier signals and their fundamental components for various implementations of timing-based power level control performed by the apparatus of. More specifically, in each of, signal generation circuitand power control circuitare shown generating carrier signaland time-adjusted carrier signal(the time-adjusted version of carrier signal) at the top of the figure, and particular implementations of carrier signal, time-adjusted carrier signal, and respective first and second fundamental components of these versions of the carrier signal, are illustrated below the signalsandin the figure.

5 FIG. 500 1 106 500 1 500 1 502 In, for example, a carrier signal-implementing carrier signalis shown to include a series of pulses having a particular timing profile. Specifically, as shown, the pulses of carrier signal-are generated at a particular frequency, generated to have a particular duty cycle (e.g., a 50% duty cycle in this example), and so forth. In this example, the series of pulses making up carrier signal-form a square wave, which, with its 50% duty cycle, may be configured to carry a maximum amount of power for an amplitudeof the carrier signal.

502 500 502 100 102 104 502 310 500 1 500 2 It will be understood that, insofar as amplituderepresents the maximum amount of power to be carried by carrier signal(at the 50% duty cycle with no skipped or modified pulses), amplituderefers to the output amplitude of the actual transmitted RF signal. However, for efficiency purposes, it will also be understood that a different amplitude may be employed by apparatus(e.g., by signal generation circuitand/or power control circuit) for purposes of generating and time-adjusting the carrier signal, and that the output amplitudemay be switched to as a final step prior to outputting wireless transmission. For example, all the signal processing involving carrier signal-and time adjustments to generate time-adjusted carrier signal-may be performed using low-voltage logic circuits (e.g., operating at 1.0 V in one example) and then, at the output stage, a level shifter may be used to bring the amplitude of the signal up to the full battery or power supply voltage (e.g., 3.6 V in one example).

502 500 1 500 2 502 500 1 502 502 500 2 100 Additionally, while amplitudeis illustrated as being the same for carrier signal-and for time-adjusted carrier signal-(thereby illustrating an implementation that may rely exclusively on timing-based power level control), it will be understood that in certain implementations, timing-based power level control may be used in combination with conventional voltage-based power level control. In such implementations, if amplitudeis the amplitude of carrier signal-, an amplitude different from amplitude(e.g., less than amplitude) may be used for time-adjusted carrier signal-to increase the potential dynamic range that may be achievable for the total amount of power ultimately delivered, as well as to enhance the controllability of the power level control performed by apparatus.

104 500 1 500 1 500 2 108 500 2 500 2 500 1 6 9 FIGS.- 5 FIG. At power control circuit, a time-adjusted version of carrier signal-is generated by adjusting the timing profile of carrier signal-to generate a time-adjusted carrier signal-that implements time-adjusted carrier signal. While specific changes to the timing profile of a standard square wave carrier signal will be illustrated inbelow, the example ofillustrates time-adjusted carrier signal-as a black box to generically represent any of various changes to the timing profile of the carrier signal that may be made for the time-adjusted version of the carrier signal. For example, as will be described and illustrated in more specific examples below, time-adjusted carrier signal-may alter the pulses of carrier signal-by symmetrically shortening certain pulses, skipping certain pulses, doing a combination of these, and/or performing other timing profile adjustments.

500 1 500 2 502 As shown, both carrier signal-and time-adjusted carrier signal-may have the same amplitude, even though, as will be further explained below, these different versions of the carrier signal may carry different amounts of power. As described above, significant benefits may arise from this feature of timing-based power level control systems described herein. By altering the amount of power by adjusting the timing profile of the carrier signal rather than the amplitude (e.g., the voltage) of the carrier signal in this way, significant flexibility may be achieved (power may be controlled using software and not requiring hardware updates) and burdensome design requirements (e.g., including a bulky buck converter and associated passive elements supporting the buck converter, etc.) may be reduced or eliminated.

500 1 504 1 500 1 106 500 1 310 500 2 504 1 500 1 5 FIG. Below carrier signal-,shows a fundamental component-associated with carrier signal-(implementing the first fundamental component described above in relation to carrier signal). Though carrier signal-may not be transmitted as output power within wireless transmission(since it is the time-adjusted version of the carrier signal, time-adjusted carrier signal-, that will be used as the output power), it will be understood that fundamental component-represents the fundamental component of carrier signal-that would result if this carrier signal were to be filtered down to its fundamental frequency (e.g., filtered to remove higher-level harmonic frequencies or overtones that give the square pulses their sharp rising and falling edges).

500 2 504 2 500 2 108 500 2 310 504 2 310 500 2 5 FIG. Similarly, below time-adjusted carrier signal-,shows a fundamental component-associated with time-adjusted carrier signal-(implementing the second fundamental component described above in relation to time-adjusted carrier signal). Since time-adjusted carrier signal-is to be used to carry output power within wireless transmission, fundamental component-may be transmitted as part of wireless transmissionafter time-adjusted carrier signal-is filtered down to its fundamental frequency by an output filter (e.g., filtered to remove the higher-level harmonic frequencies or overtones that give the pulses their sharp rising and falling edges).

504 1 504 2 506 508 504 1 504 2 510 504 1 512 504 2 500 2 506 508 500 2 512 500 1 510 5 FIG. As shown, both fundamental components-and-share a same frequency(represented by a time between successive peaks on the sinusoidal signal) and a same phase(represented by a relative timing position of the peaks of the signals which does not shift one way or the other from fundamental component-to fundamental component-). However, as further shown in, an amplitudeof fundamental component-is different from an amplitudeof fundamental component-. This is due to the modifications to the timing profile of time-adjusted carrier signal-to reduce the duty cycle of certain pulses, to skip certain pulses, and so forth. Even though these modifications are made in a way that allows the fundamental frequencyand the fundamental phaseto be maintained, the amount of power carried by time-adjusted carrier signal-(represented by amplitude) is reduced from the maximum amount of power carried by carrier signal-(represented by amplitude).

310 500 2 512 314 510 314 512 510 6 9 FIGS.- As will now be described in more detail, the amount of output power provided on wireless transmission(carried by time-adjusted carrier signal-and represented by amplitude) may be controlled with a great degree of precision and flexibility using a wide array of different timing profile patterns represented by different timing control datasetsthat may be used. While it may not be possible to achieve every possible power level from the maximum supported power level (represented by amplitude) down to zero, a large number of discrete power levels (e.g., dozens or hundreds of potential power levels) may be achieved between the maximum supported power level and a power level of zero by leveraging different combinations and patterns of skipped pulses, shortened pulses, and so forth. These combinations and patterns may be stored as different timing control datasetsand may result in a wide array of different amplitudesthat range from amplitudedown to zero. Certain of these combinations and patterns will now be described in relation to.

6 FIG. 5 FIG. 106 600 1 108 600 2 602 600 1 600 1 600 1 600 2 In, carrier signalis implemented by a carrier signal-, and time-adjusted carrier signalis implemented by a time-adjusted carrier signal-, both of which have a same amplitude. As with the example of, carrier signal-includes a series of pulses generated at a particular frequency, and the timing profile of the carrier signal is adjusted for the time-adjusted version of the carrier signal. Specifically, the timing profile of carrier signal-is adjusted in this example by skipping a sub-series of pulses from the series of pulses. The sub-series of pulses has a frequency lower than the particular frequency of carrier signal-. For instance, as shown in this example, the sub-series of pulses that are skipped includes every other pulse, thus making the frequency of the sub-series half of the particular frequency in this example. It will be understood that in other examples (not shown), every third pulse, every fourth pulse, two out of every five pulses, or another suitable pattern of pulses may be skipped in the way illustrated for every other pulse in time-adjusted carrier signal-.

5 FIG. 604 1 600 1 606 608 604 2 600 2 604 1 610 604 2 612 610 308 600 2 612 604 2 610 604 1 Similarly as described above in relation to, a fundamental component-corresponding to carrier signal-is characterized by a frequencyand a phasethat are the same as the frequency and phase characterizing a fundamental component-corresponding to time-adjusted carrier signal-. However, while fundamental component-is characterized by an amplitudeassociated with a maximum power level, fundamental component-is characterized by an amplitudethat is less than amplitudeand is associated with a reduced power level (e.g., whatever power level is desired for a particular scenario as called for by target power levelin the ways described above). In this particular example in which every other pulse is skipped for time-adjusted carrier signal-, for instance, the power level corresponding to amplitudeof fundamental component-may be approximately 25% of the power level corresponding to amplitudeof fundamental component-.

7 FIG. 5 6 FIGS.- 106 700 1 108 700 2 702 700 1 700 1 700 1 700 2 As another example, incarrier signalis implemented by a carrier signal-, and time-adjusted carrier signalis implemented by a time-adjusted carrier signal-, both of which have a same amplitude. As with the examples of, carrier signal-includes a series of pulses generated at a particular frequency, and the timing profile of the carrier signal is adjusted for the time-adjusted version of the carrier signal. Specifically, the timing profile of carrier signal-is adjusted in this example by symmetrically shortening a sub-series of pulses from the series of pulses. The sub-series of pulses symmetrically shortened may have a frequency lower than or equal to the particular frequency of carrier signal-. For instance, as shown in this example, the sub-series of pulses that are symmetrically shortened includes every other pulse, thus making the frequency of the sub-series of pulses half of the particular frequency. It will be understood that in other examples (not shown), every third pulse, every fourth pulse, two out of every five pulses, or another suitable pattern of pulses may be symmetrically shortened in the way illustrated for every other pulse in time-adjusted carrier signal-. In still other examples, every pulse could be symmetrically shortened, such that the frequency of the sub-series of pulses would be equal to the particular frequency of the series of pulses (rather than less than the particular frequency, as with the other examples mentioned).

5 6 FIGS.- 704 1 700 1 706 708 704 2 700 2 704 1 710 704 2 712 710 308 610 710 712 612 600 2 700 2 Similarly as described above in relation to, a fundamental component-corresponding to carrier signal-is characterized by a frequencyand a phasethat are the same as the frequency and phase characterizing a fundamental component-corresponding to time-adjusted carrier signal-. However, while fundamental component-is characterized by an amplitudeassociated with a maximum power level, fundamental component-is characterized by an amplitudethat is less than amplitudeand is associated with a reduced power level (e.g., whatever power level is desired for a particular scenario as called for by target power levelin the ways described above). It will be understood that even if amplitudesandare a same amplitude corresponding to a same maximum power level, amplitudemay be different from amplitudesince the different timing profiles applied to time-adjusted carrier signals-and-may correspond to different power levels of the large plurality of supported power levels described above.

8 FIG. 5 7 FIGS.- 106 800 1 108 800 2 802 800 1 800 1 800 1 800 2 As yet another example, incarrier signalis implemented by a carrier signal-, and time-adjusted carrier signalis implemented by a time-adjusted carrier signal-, both of which have a same amplitude. As with the examples of, carrier signal-includes a series of pulses generated at a particular frequency, and the timing profile of the carrier signal is adjusted for the time-adjusted version of the carrier signal. Specifically, the timing profile of carrier signal-is adjusted in this example by a combination of skipping a first sub-series of pulses from the series of pulses, and symmetrically shortening a second sub-series of pulses from the series of pulses. The first sub-series of pulses that is skipped may have a first frequency lower than the particular frequency. For instance, as shown in this example, the first frequency of the first sub-series may be one-fourth the particular frequency such that every fourth pulse is skipped. The second sub-series of pulses may have a second frequency lower than or equal to a difference between the particular frequency of carrier signal-and the first frequency. For instance, as shown in this example, the second frequency of the second sub-series may be one-fourth the particular frequency such that every fourth pulse is shortened (a different pulse than the one that is skipped). In other examples, the second frequency of the second sub-series could be as high as three-fourths of the particular frequency such that three out of every four pulses (e.g., every pulse that is not skipped due to being part of the first sub-series) are shortened. As has been described, various other patterns of skipped and symmetrically shortened pulses may be implemented in similar ways as illustrated for time-adjusted carrier signal-. In all of these examples, it will be understood that the first and second sub-series of pulses are non-overlapping such that each pulse is either skipped, shortened, or left unmodified (but not more than one of these).

5 7 FIGS.- 804 1 800 1 806 808 804 2 800 2 804 1 810 804 2 812 810 308 610 710 810 612 712 812 600 2 700 2 800 2 Similarly as described above in relation to, a fundamental component-corresponding to carrier signal-is characterized by a frequencyand a phasethat are the same as the frequency and phase characterizing a fundamental component-corresponding to time-adjusted carrier signal-. However, while fundamental component-is characterized by an amplitudeassociated with a maximum power level, fundamental component-is characterized by an amplitudethat is less than amplitudeand is associated with a reduced power level (e.g., whatever power level is desired for a particular scenario as called for by target power levelin the ways described above). It will be understood that even if amplitudes,, andare a same amplitude corresponding to a same maximum power level, amplitudes,, andmay be different from one another since the different timing profiles applied to time-adjusted carrier signals-,-, and-may correspond to different power levels of the large plurality of supported power levels described above.

9 FIG. 5 8 FIGS.- 106 900 1 108 900 2 902 900 1 900 1 900 1 900 1 900 1 900 1 900 2 As yet another example, incarrier signalis implemented by a carrier signal-, and time-adjusted carrier signalis implemented by a time-adjusted carrier signal-, both of which have a same amplitude. As with the examples of, carrier signal-includes a series of pulses generated at a particular frequency, and the timing profile of the carrier signal is adjusted for the time-adjusted version of the carrier signal. Specifically, the timing profile of carrier signal-is adjusted in this example by a combination of symmetrically shortening a first sub-series of pulses from the series of pulses by a first amount and symmetrically shortening a second sub-series of pulses from the series of pulses by a second amount distinct from the first amount. The first sub-series of pulses shortened by the first amount may have a first frequency lower than the particular frequency of carrier signal-. For instance, as shown in this example, the first frequency of the first sub-series may be one-half the particular frequency such that every other pulse is shortened by a first amount (e.g., a relatively small amount such that these pulses are only slightly narrower than the pulses of carrier signal-). The second sub-series of pulses shortened by the second amount may have a second frequency that is also lower than the particular frequency of carrier signal-. For instance, as shown in this example, the second frequency of the second sub-series may also be one-half the particular frequency so that pulses shortened by shortened by the second amount (e.g., a relatively large amount such that these pulses are more significantly narrower than the pulses of carrier signal-) are interleaved with the pulses of the first sub-series. Various other patterns of skipped and symmetrically shortened pulses of varying pulse widths may be implemented in similar ways as illustrated for time-adjusted carrier signal-. In all of these examples, it will be understood that various sub-series of pulses may be non-overlapping such that each pulse is either skipped, shortened by one amount or another, or left unmodified.

5 8 FIGS.- 904 1 900 1 906 908 904 2 900 2 904 1 910 904 2 912 910 308 610 710 810 910 612 712 812 912 600 2 700 2 800 2 900 2 Similarly as described above in relation to, a fundamental component-corresponding to carrier signal-is characterized by a frequencyand a phasethat are the same as the frequency and phase characterizing a fundamental component-corresponding to time-adjusted carrier signal-. However, while fundamental component-is characterized by an amplitudeassociated with a maximum power level, fundamental component-is characterized by an amplitudethat is less than amplitudeand is associated with a reduced power level (e.g., whatever power level is desired for a particular scenario as called for by target power levelin the ways described above). It will be understood that even if amplitudes,,, andare a same amplitude corresponding to a same maximum power level, amplitudes,,, andmay be different from one another since the different timing profiles applied to time-adjusted carrier signals-,-,-, and-may correspond to different power levels of the large plurality of supported power levels described above.

310 302 304 100 310 108 500 2 600 2 700 2 800 2 900 2 As has been mentioned, wireless transmissionmay be used to deliver not only power, but also data from an external component of a medical system (e.g., external component) to an internal component (e.g., internal component). For example, output data based on input data provided to apparatusmay be delivered to the internal component by being modulated onto the time-adjusted version of the carrier signal that is being transmitted in wireless transmission(e.g., time-adjusted carrier signalor an implementation thereof such as time-adjusted carrier signal-,-,-,-, or-).

310 100 104 100 108 108 108 512 612 712 812 912 512 612 712 812 912 To include such output data within wireless transmission, apparatus(e.g., power control circuitwithin apparatus) may be configured to generate time-adjusted carrier signalin a manner that modulates the output data onto time-adjusted carrier signalby causing the second fundamental component (i.e., the fundamental component of time-adjusted carrier signal) to have different amplitudes at different times. Specifically, for a first binary value of the output data (e.g., a ‘HIGH’ value, a ‘1’ value, etc.), the second fundamental component may have the second amplitude associated with the target power level (e.g., any of amplitudes,,,, or, or another suitable amplitude from the plurality of potential amplitudes attainable using the different timing profiles described above). Then, for a second binary value of the output data (e.g., a ‘LOW’ value, a ‘0’ value, etc.), the second fundamental component may have a third amplitude lower than the second amplitude associated with the target power level. For instance, as will now be described and illustrated, this third amplitude may be an amplitude of zero to implement an On-Off Keying (OOK) modulation protocol, or may be a non-zero amplitude such as a different one of amplitudes,,,, or(or another suitable amplitude from the plurality of potential amplitudes attainable using the different timing profiles described above) to implement an Amplitude Shift Keying (ASK) modulation protocol.

10 11 FIGS.- 10 FIG. 11 FIG. To illustrate,show illustrative ways that output data may be modulated onto a carrier signal (e.g., a time-adjusted version of the carrier signal) for wireless transmission of power in accordance with timing-based power level control implementations described herein. Specifically,shows an implementation employing an OOK modulation protocol whileshows an implementation employing an ASK modulation protocol.

10 FIG. 1002 1004 1006 1006 1 1006 2 1006 1008 1008 1 1010 1012 1 1008 1 1014 1008 1 1004 1006 1 1018 1020 Referring first to, various waveforms are shown in relation to a timeline. For example, a data waveformis shown to include different binary valuessuch as a HIGH binary value-(representing a binary ‘1’) and a LOW binary value-(representing a binary ‘0’). Drawn below binary valuesare different versions of a time-adjusted carrier signal. Specifically, a first time-adjusted carrier signal-is shown to have a first amplitudeand to include a series of pulses that may comport with any of the timing profiles described herein (e.g., including skipped, shortened, unmodified, and/or other pulses as may serve a particular implementation). As shown, a fundamental component-corresponding to time-adjusted carrier signal-is shown to have a particular amplitudethat is associated with a power level carried by time-adjusted carrier signal-while data waveformcarries the HIGH binary value-, as well as a particular frequencyand a particular phase.

10 FIG. 1004 1006 2 1008 2 1006 2 1012 2 1008 2 1016 1016 Becauseillustrates an OOK modulation protocol, when data waveformcarries the LOW binary value-, a second time-adjusted carrier signal-is shown to have an amplitude of 0. In other words, in the On-Off Keying modulation protocol, the carrier signal is completely shut off while transmitting a LOW binary value-and a fundamental component-corresponding to the zero-amplitude time-adjusted carrier signal-is likewise shown to have an amplitudeof zero, corresponding to a power level of zero. Hence, in this OOK modulation example, the third amplitude (amplitude) is implemented as an amplitude of zero that is used within the OOK modulation protocol to implement the modulating of the output data onto the time-adjusted version of the carrier signal.

11 FIG. 10 FIG. 11 FIG. 1102 1104 1106 1106 1 1106 2 1106 1108 1108 1 1110 1112 1 1108 1 1114 1108 1 1104 1106 1 1118 1120 In contrast,illustrates an example in which the third amplitude is a non-zero amplitude (e.g., an amplitude associated with an additional timing profile of the carrier signal distinct from the timing profile used to cause the second fundamental component of the original carrier signal to have the second amplitude) used within an ASK modulation protocol to implement the modulating of the output data onto the time-adjusted version of the carrier signal. Similar to,shows various waveforms in relation to a timeline. For example, a data waveformis shown to include different binary valuessuch as a HIGH binary value-(representing a binary ‘1’) and a LOW binary value-(representing a binary ‘0’). Drawn below binary valuesare different versions of a time-adjusted carrier signal. Specifically, a first time-adjusted carrier signal-is shown to have a first amplitudeand to include a series of pulses that may comport with any of the timing profiles described herein (e.g., including skipped, shortened, unmodified, and/or other pulses as may serve a particular implementation). As shown, a fundamental component-corresponding to time-adjusted carrier signal-is shown to have a particular amplitudethat is associated with a power level carried by time-adjusted carrier signal-while data waveformcarries the HIGH binary value-, as well as a particular frequencyand a particular phase.

11 FIG. 1104 1106 2 1108 2 1110 1106 2 314 1112 2 1108 2 1116 1114 1116 1114 Becauseillustrates an ASK modulation protocol, when data waveformcarries the LOW binary value-, a second time-adjusted carrier signal-is shown to have the same amplitude, but to employ a different timing protocol (e.g., a timing protocol in which more pulses are skipped or shortened, etc.). As such, for this Amplitude-Shift Keying modulation protocol, the carrier signal is remains active while transmitting a LOW binary value-, but uses a different timing protocol (e.g., associated with a different timing control dataset) such that a fundamental component-corresponding to the time-adjusted carrier signal-is shown to have an amplitudethat is non-zero, but is lower than amplitude. Amplitudemay correspond to a power level lower than the power level associated with amplitude.

104 104 104 314 308 104 104 As mentioned above, maintaining the frequency and phase of the fundamental component of a carrier signal while reducing the amplitude may be performed by adjusting the duty cycle of a pulse in a manner referred to herein as symmetrically shortening the pulse. This duty cycle adjustment moves rising and falling edges of a pulse symmetrically inward toward one another in a manner that maintains the timing of zero crossings of the fundamental component so as to maintain the phase as has been described and illustrated. Symmetric shortening of the pulses of a carrier signal may be achieved in any suitable way. For instance, in one implementation, power control circuitmay include a delay circuit (e.g., a voltage-controlled delay line circuit, etc.) that inputs the carrier signal and outputs an array of delayed versions of the carrier signal. Power control circuitmay then be configured to generate the time-adjusted version of the carrier signal by performing certain operations such as the following. Power control circuitmay select a first delayed version and a second delayed version of the carrier signal from the array of delayed versions of the carrier signal. For instance, the first and second delayed versions may be selected based on the timing control data (e.g., whatever signals are indicated by an identified timing control datasetfor a given target power level). Power control circuitmay then generate the time-adjusted version of the carrier signal based on the selected first and second delayed versions of the carrier signal. For example, power control circuitmay use logic to create a rising edge on the time-adjusted carrier signal for each rising edge of the first delayed version of the carrier signal and to create a falling edge on the time-adjusted carrier signal for each falling edge of the second delayed version of the carrier signal.

12 FIG. 12 FIG. 12 FIG. 12 FIG. To illustrate,shows certain aspects of this particular way of generating the time-adjusted version of the carrier signal for use within timing-based power level control implementations described herein. It will be understood that the manner of symmetrically shortening pulses of a carrier signal described above and shown inare not the only ways that symmetric shortening of a series of pulses may be performed and that various other ways may be used as an alternative to the novel technique shown. Additionally, it will be understood that, whileshows a technique for generating a time-adjusted carrier signal in which every pulse is symmetrically shortened by the same amount, related techniques or other techniques may be employed to implement some of the other timing profiles described herein (e.g., in which only some but not all of the pulses are shortened, in which different pulses are shortened by different amounts, in which certain pulses are skipped, etc.). For instance, one way of implementing a more complex timing profile may be to duplicate the technique ofto generate a variety of intermediate time-adjusted carrier signals in which the pulses are shortened by different amounts, and then multiplexing these intermediate signals together according to certain timing parameters so as to generate a final time-adjusted carrier signal (e.g., a signal that shortens different pulses by different amounts in accordance with a desired timing profile). In some examples, a zero-amplitude signal (e.g., ground) may also be multiplexed together to add skipped pulses to the timing profile as may serve a particular implementation.

12 FIG. 1200 1202 1202 1202 108 108 In accordance with the description above,shows a symmetric pulse shortening circuitthat inputs a carrier signal-In and outputs a time-adjusted version of the carrier signal referred to as time-adjusted carrier signal-Out. It will be understood that time-adjusted carrier signal-Out may correspond to time-adjusted carrier signalin certain scenarios or may serve as an intermediary signal to generate an implementation of time-adjusted carrier signalin other examples (as has been described).

1202 1202 1200 1204 1202 1202 1206 1206 1206 1 1206 12 1206 1204 1204 To generate time-adjusted carrier signal-Out based on carrier signal-In, circuitincludes a delay circuitthat takes in carrier signal-In and outputs a plurality of delayed versions of carrier signal-In referred to as delayed carrier signals. In this example, twelve delayed carrier signalsare shown (i.e., delayed carrier signals-through-), but it will be understood that twelve is only an example and other implementations may provide more or fewer delayed carrier signalsto achieve a desired amount of resolution. A delay circuit used to implement delay circuitmay be fully compatible with integrated circuits and may be made controllable through an adjustable bias current, or an adjustable capacitive load such as with a varactor. Delay circuitmay be further calibrated using an available time base with a delay-locked loop (DLL). For example, a DLL with a digitally programmable voltage-controlled delay line (VCDL) may be used to calibrate the delay elements of a delay line, and then replica delay lines may be used to digitally select the length of the line and adjust the delay of each element to generate pulse start and stop signals corresponding to the desired duty cycle (or pulse width), and time shift for driving an RF transmitter.

1206 1202 1208 312 1210 1206 314 312 1208 1206 1206 3 1202 1208 1206 1206 10 1202 1210 1208 1206 3 1210 1208 1206 10 12 FIG. 12 FIG. As shown, delayed carrier signalsare delayed by amounts that are evenly distributed along the period of carrier signal-In so as to create twelve copies of the carrier signal that have different phases evenly distributed between 0° and 360° (a full cycle of the carrier signal). Control datamay be accessed from storage facilityfor use by two multiplexorsto select two of delayed carrier signals. For instance, a particular timing control datasetstored in storage facilitymay include data indicative of first control data-R indicative of one of delayed carrier signals(e.g., signal-in this example, as indicated by the “(3)” in) that is to control the rising edge of time-adjusted carrier signal-Out, as well as second control data-F indicative of a different one of delayed carrier signals(e.g., signal-in this example, as indicated by the “(10)” in) that is to control the falling edge of time-adjusted carrier signal-Out. Accordingly, as shown, a rising edge multiplexor (mux)-R controlled by control data-R is shown to output delayed carrier signal-, while a falling edge multiplexor (mux)-F controlled by control data-F is shown to output delayed carrier signal-.

1208 1202 1202 1206 3 1206 10 314 1208 312 1206 2 1206 11 1206 4 1206 9 1206 5 1206 8 It is noted that timing control datamay be preconfigured so as to always select delayed carrier signals that are symmetrically related so as to ensure that pulses of time-adjusted carrier signal-Out will be symmetrically shortened pulses corresponding to the pulses of carrier signal-In (and thereby maintain the same phase for the fundamental component, as has been described). For example, instead of delayed carrier signals-and-, a different timing control dataset(i.e., different timing control data) accessed from storage facilitymay select delayed carrier signals-and-, or-and-, or-and-, or another such symmetrical pair as may serve a particular implementation.

1212 1206 1206 3 1206 10 1202 1212 1202 1206 3 1206 10 1206 1210 1206 3 1206 1210 1206 10 1206 10 1202 1202 1202 1202 310 1206 1202 Logicmay input the selected delayed carrier signals(e.g., delayed carrier signals-and-in this example) and combine them to form time-adjusted carrier signal-Out in any suitable way. For instance, in this example, logicmay be implemented by an AND gate, since time-adjusted carrier signal-Out is shown to be HIGH when delayed carrier signals-and-are both HIGH and to be LOW otherwise. In other examples, other logic could be implemented such as to invert (NOT) the delayed carrier signalcoming from falling edge multiplexor-F (e.g., signal-) prior to its entry into an AND gate with the delayed carrier signalcoming from rising edge multiplexor-R (e.g., signal-). In this way, it would be the rising edge (rather than the falling edge) of delayed carrier signal-that would instigate the falling edge of time-adjusted carrier signal-Out and the pulses of time-adjusted carrier signal-Out would have a different pulse width (as well as a different phase from carrier signal-In, though different time-adjusted carrier signals-Out generated in this way for an ASK modulation protocol would have the same phase as one another such that wireless transmissionwould maintain a consistent phase). In still other examples, other logic may be utilized such as a set/reset (SR) latch or flip-flop or other suitable logic configured to combine the selected delayed carrier signalsto generate time-adjusted carrier signal-Out in any manner as may serve a particular implementation.

In the preceding description, various illustrative embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the scope of the invention as set forth in the claims that follow. For example, certain features of one embodiment described herein may be combined with or substituted for features of another embodiment described herein. The description and drawings are accordingly to be regarded in an illustrative rather than a restrictive sense.